Small cases or boxes for jewelry, stationary, cigars, fishing flies and the like have long used hinges for attaching case tops and bottoms. It is desirable for such hinges to be attractive, consistently functional, economical, and easy to install in small wooden cases with relatively little effort and cost.
Hinges for this purpose typically use a pair of dowel-like hinge members joined by a pin or rivet extending completely through the members to provide a hinge axis about which the members pivot. The two dowel-like members usually have different but complementary shapes that are secured by a fastener or rivet extending completely through an aperture in each hinge member. For example, the first hinge member may have a cylindrical head from which a rectangular section has been removed. The second hinge member would then have a rectangular head of substantially the same dimensions as the rectangular section removed from the first hinge member. The head of one member is received in the recessed portion of the second member, and a fastener extends through both members.
This hinge design has several disadvantages. It is expensive to manufacture because two different hinge members are needed. Because the hinge members are different, additional installation time is required to ensure proper and consistent orientation of adjacent hinges. Other problems arise where the fastener extends completely through the hinge members and remains visible. A visible fastener often detracts from the beauty of the hinge. A solution to this aesthetic problem has been to grind down the protruding fastener until it is flush with the hinge surface. This is unsatisfactory however, because in addition to the extra manufacturing cost, grinding down the fastener can mar the hinge member.
In a more recent example of the general dowel-like hinge design used for small wooden cases, a pair of identical hinge members are secured together by a fastener extending completely through an aperture in each hinge member. Similar disadvantages exist for this hinge design as well. Although only one type of hinge member needs to be manufactured, additional operations are required to fasten the two identical hinge members together. For instance, the aperture in one of the hinge members would need to be enlarged to properly secure the two hinge members with a fastener. The fastener also needs to be counter-sunk in hinge members. All of these machining operations increase the cost of manufacturing this type of hinge. In addition, the aesthetic problems previously described with respect to the fastener extending completely through the hinge body have not been addressed.
In the design and manufacturing of small wooden cases, it is desirable to drill blind holes or mortises in the case so the hinge members may be partially inserted into the case top and bottom to enable the lid to close tightly, as well as make the hinge installation attractive. This can be accomplished by marking the hinge location on the case top and case bottom and cutting or drilling a mortise at each location so the hinge member can be inserted into the case wall. This method is time consuming, requires substantial skill, and often results in hinge members that are mis-aligned, which causes case tops to open unsatisfactorily.
Another method has been to drill a hole nearly the entire vertical length of the case through the bottom of the case prior to separating the case into a top and bottom portion. Then the case is sawed in two at the case parting line separating the top from the bottom. Because of the length of the hole or mortise required by this method, the drill often wanders. When this occurs, the case wall is weakened or may even be pierced. In addition, two or more hinges installed in this manner may be mis-aligned.
For the reasons explained above, there is a need for a hinge that is attractive, economical, consistently functional, and that may be installed in small wooden cases with relatively little effort and cost. There is also a need for an apparatus for efficiently and accurately forming blind holes or mortises in cases for inserting hinge members.